According to a method of the existing art (see 1993 Leica brochure of Leica Aktiengesellschaft, Vienna, Austria), it is proposed to perform a cryosubstitution in special flow-through capsules (Reichert™). Embedding of the specimen for producing thin sections is then also accomplished in the same capsules. A method for the preparation of thin sections of cellular monolayers is not presented here. In addition, the container of the specimens for cryosubstitution disclosed in the existing art cannot successfully guarantee the cryosubstitution of cellular monolayers.